如何动态更新插入查询。 SQL-PHP-笨

I want to dynamically add new columns and its value for new registered users. I am trying explain you in details.

I have a query of data insertmysqli_query($con, "Insert into tbl_name ('id', 'name') VALUES('', '".$name."')") id is auto-increment. Now I am adding one more filed to this tbl_name. like Fname and default value is NULL. So every records got this field with NULL value. Now, If new user comes to website and he/she wants to join this site.then need to register.

So When they try to register, He/She gets old Insert query. But newly added column is not there in old insert query.

New query should look like this mysqli_query($con, "Insert into tbl_name('id', 'name', 'F_Name') VALUES('', '".$name."', '".$F_Name."')") So I want to update Old insert query to new dynamically, Is it possible.?

If it is possible then please tell me.